Method for producing hydroxylamine compound using platinum catalyst fixed on ion-exchange resin

ABSTRACT

The present invention discloses a method for producing a hydroxylamine compound wherein a nitro compound is contacted with a hydrogen source or further with a poisoning agent in the presence of a platinum catalyst fixed on an ion-exchange resin. According to the method of the present invention where a platinum catalyst fixed on a matrix of an ion-exchange resin is used, the objective hydroxylamine compound can be produced (manufactured) efficiently, more industrially and safely with little formation of a byproduct. Further, the platinum catalyst fixed on an ion-exchange resin of the present invention is hardly deactivated even if repeatedly used many times because platinum metal is fixed on a matrix of the ion-exchange resin, and handling in recovery, reuse and the like of said catalyst is extremely easy because particle size of said catalyst is very large.

TECHNICAL FIELD

The present invention relates to a method for producing a hydroxylaminecompound from a nitro compound using a platinum catalyst fixed on anion-exchange resin.

BACKGROUND

Hydroxylamine compounds are very important compounds as intermediateproducts for, for example, polymerization inhibitors, antioxidants,agricultural chemicals, medicines, cosmetics and electronic industrialchemicals.

Phenylhydroxylamine as an example of the hydroxylamine compound is auseful compound as an intermediate product for polymerization inhibitorsand antioxidants, and had been conventionally manufactured by a methodwhere nitrobenzene is reduced with sodium hydrosulfide or a method wherenitrobenzene is reacted with hydrogen using a platinum-carbon catalyst(see, U.S. Pat. No. 3,694,509).

However, in the former method, yield of an objective product is not highenough to be practically used due to a low selectivity of the reaction,and there is fear that offensive odor of sodium hydrosulfide to be usedaffect working environment.

On the other hand, in the latter method, yield of an objective productis not high enough to be commercially used similarly to the formermethod, and there is a problem that elevation of reaction temperature toimprove the yield results in, on the contrary, lowering of the yield dueto decrease of reaction selectivity. Further, in the latter method, notonly formation ratio of aniline as a byproduct is high but alsoplatinum-carbon to be used as a reaction catalyst requires specialattention in handling because of a combustible substance. Still further,recovery and reuse of the above platinum catalyst after use requiresextremely complicated procedures due to a very small particle size.

Under the above circumstances, development of a method for manufacturing(producing) a hydroxylamine compound efficiently, industrially andsafely is demanded.

DISCLOSURE OF THE INVENTION

The present invention provides a method for producing a hydroxylaminecompound, wherein a nitro compound is contacted with a hydrogen sourcein the presence of a platinum catalyst fixed (immobilized) on anion-exchange resin.

That is, the present inventors, after extensively studied to solve theabove problems, have found that the objective hydroxylamine compound canbe obtained efficiently, industrially and safely by using a catalystwhere a platinum metal is fixed (supported) on a matrix of anion-exchange resin, namely, a platinum catalyst fixed on an ion-exchangeresin, and the catalyst fixed on the ion-exchange resin is not only easyto handle but also easy to recover and reuse due to a large particlesize thereof, and completed the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

A platinum catalyst fixed on an ion-exchange resin of the presentinvention is one that can be obtained by adsorbing a platinum-containingion in an aqueous solvent with a suitable ion-exchange resin followed bysubjecting the ion to a reductive treatment. In said catalyst, theplatinum metal is fixed on a matrix of the ion-exchange resin. Here, theplatinum-containing ion means an anion or a cation derived from aplatinum compound or a platinum complex which contains, for example, 1-to 6-valent, more specifically bivalent, tetravalent and hexavalentplatinum ions or platinum atom.

When the platinum catalyst fixed on an ion-exchange resin of the presentinvention is obtained, a platinum compound to be dissolved in theaqueous solvent in order to make the platinum-containing ion present inthe aqueous solvent includes, for example, platinum metal, platinumoxides such as PtO₂; platinum halides such as platinum chloride,platinum bromide and platinum iodide; ammonium platinates such asammonium hexachloroplatinate and ammonium tetrachloroplatinate;potassium halogenated platinates such as potassium hexachloroplatinate,potassium tetrachloroplatinate and potassium tetrabromoplatinate; sodiumhalogenated platinates such as sodium hexachloroplatinate and sodiumtetrachloroplatinate; platinum nitrate; platinum sulfate; platinumacetate; and platinum complexes coordinated with a ligand. Among others,potassium halogenated platinates and sodium halogenated platinates arepreferable, and potassium tetrachloroplatinate and sodiumtetrachloroplatinate are particularly preferable.

The ligand of the platinum complexes coordinated with a ligand includes,for example, 1,5-cyclooctadiene (COD), dibenzylideneacetone (DBA),norbornadiene (NBD), tricyclohexylphosphine (PCy₃), triethoxyphosphine(P(OEt)₃), tri-tert-butylphosphine (P(O^(t)Bu)₃), bipyridine (BPY),phenanthroline (PHE), triphenylphosphine (PPh₃),1,2-bis(diphenylphosphino)ethane (DPPE), triphenoxyphosphine (P(OPh)₃),trimethoxyphosphine (P(OCH₃)₃), ethylene (CH₂═CH₂), amine(NH₃), N₂ andPO₃.

When the platinum catalyst fixed on an ion-exchange resin of the presentinvention is obtained, the ion-exchange resin to be used includes oneconsisting of a so-called skeletal polymer to which an ion-exchangegroup bonded. Said skeletal polymer includes, for example, one obtainedby polymerizing or copolymerizing a monomer represented by the followinggeneral formula [1]:

(wherein, R and R¹ represent each independently a hydrogen atom, a loweralkyl group, a carboxyl group, a carboxyalkyl group, an alkyloxycarbonylgroup, a hydroxyalkyloxycarbonyl group, a cyano group or a formyl group;R² represents a hydrogen atom, a lower alkyl group, a carboxyl group, analkyloxycarbonyl group, a hydroxyalkyloxycarbonyl group, a cyano groupor a halogen atom; R³ represents a hydrogen atom, a lower alkyl group, ahaloalkyl group, a hydroxyl group, an aryl group which may have asubstituent, an aliphatic heterocyclic group, an aromatic heterocyclicgroup, a halogen atom, an alkyloxycarbonyl group, ahydroxyalkyloxycarbonyl group, a sulfo group, a cyano group, acyano-containing alkyl group, an acyloxy group, a carboxyl group, acarboxyalkyl group, an aldehyde group, an amino group, an aminoalkylgroup, a carbamoyl group, a N-alkylcarbamoyl group or a hydroxyalkylgroup; and R and R⁴ or R¹ and R² may form an aliphatic ring togetherwith the adjacent —C═C— bond).

The lower alkyl group represented by R and R¹ to R³ in the generalformula [1] may be straight chained, branched or cyclic, and includes,for example, an alkyl group having 1 to 6 carbon atoms, and isspecifically exemplified by a methyl group, an ethyl group, a n-propylgroup, an isopropyl group, a n-butyl group, an isobutyl group, atert-butyl group, a sec-butyl group, a n-pentyl group, an iso-pentylgroup, a tert-pentyl group, a 1-methylpentyl group, a n-hexyl group, aniso-hexyl group, a cyclopropyl group, a cyclopentyl group and acyclohexyl group.

The carboxyalkyl group represented by R, R¹ and R² includes, forexample, one where a part of hydrogen atoms of the above-described loweralkyl group is replaced by a carboxyl group, and is specificallyexemplified by, for example, a carboxymethyl group, a carboxyethylgroup, a carboxypropyl group, a carboxybutyl group, a carboxypentylgroup and a carboxyhexyl group.

The alkyloxycarbonyl group represented by R and R¹ to R³ preferablyincludes, for example, one having 2 to 11 carbon atoms, and isspecifically exemplified by, for example, a methoxycarbonyl group, anethoxycarbonyl group, a propoxycarbonyl group, a butoxycarbonyl group, apentyloxycarbonyl group, a hexyloxycarbonyl group, a heptyloxycarbonylgroup, a 2-ethylhexyloxycarbonyl group, a octyloxycarbonyl group, anonyloxycarbonyl group and a decyloxycarbonyl group.

The hydroxyalkyloxycarbonyl group represented by R and R¹ to R³ includesone where a part of hydrogen atoms of the above-describedalkyloxycarbonyl group is replaced by a hydroxyl group, and isspecifically exemplified by, for example, a hydroxymethyloxycarbonylgroup, a hydroxyethyloxycarbonyl group, a hydroxypropyloxycarbonylgroup, a hydroxybutyloxycarbonyl group, a hydroxypentyloxycarbonylgroup, a hydroxyhexyloxycarbonyl group, a hydroxyheptyloxycarbonylgroup, a hydroxyoctyloxycarbonyl group, a hydroxynonyloxycarbonyl groupand a hydroxydecyloxycarbonyl group.

The halogen atom represented by R² and R³ includes, for example,fluorine, chlorine, bromine and iodine.

The haloalkyl group represented by R³ includes, for example, theabove-described lower alkyl group having 1 to 6 carbon atoms representedby R¹ to R³ which is halogenated (for example, fluorinated, chlorinated,brominated and iodinated), and is specifically exemplified by, forexample, a chloromethyl group, a bromomethyl group, a trifluoromethylgroup, a 2-chloroethyl group, a 3-chloropropyl group, a 3-bromopropylgroup, a 3,3,3-trifluoropropyl group, a 4-chlorobutyl group, a5-chloropentyl group and a 6-chlorohexyl group.

The aryl group of the aryl group which may have a substituent includes,for example, a phenyl group, a tolyl group, a xylyl group and a naphthylgroup, and said substiutent includes, for example, an amino group, ahydroxyl group, a lower alkoxy group and a carboxyl group. Specificexamples of the substituted aryl group include, for example, anaminophenyl group, a toluidino group, a hydroxyphenyl group, amethoxyphenyl group, a tert-butoxyphenyl group and a carboxyphenylgroup.

The aliphatic heterocyclic group preferably includes, for example,5-membered or 6-membered one containing 1 to 3 hetero atoms such as anitrogen atom, an oxygen atom and a sulfur atom, and is exemplified by,for example, a pyrolidil-2-on group, a pyperidyl group, a pyperidinogroup, a pyperadinyl group and a morpholino group.

The aromatic heterocyclic group preferably includes, for example,5-membered or 6-membered one containing 1 to 3 hetero atoms such as anitrogen atom, an oxygen atom and a sulfur atom, and is exemplified by,for example, a pyridil group, an imidazolyl group, a thiazolyl group, afuranyl group and a piranyl group.

The cyano-containing alkyl group includes, for example, one where a partof hydrogen atoms of the above-described lower alkyl group is replacedby a cyano group, and is exemplified by, for example, a cyanomethylgroup, a 2-cyanoethyl group, a 2-cyanopropyl group, a 3-cyanopropylgroup, a 2-cyanobutyl group, a 4-cyanobutyl group, a 5-cyanopentyl groupand a 6-cyanohexyl group.

The acyloxy group includes, for example, one derived from a carboxylicacid having 2 to 20 carbon atoms, and is specifically exemplified by,for example, an acetyloxy group, a propionyloxy group, a butylyloxygroup, a pentanoyloxy group, a nonanoyloxy group, a decanoyloxy groupand a benzoyloxy group.

The aminoalkyl group includes one where a part of hydrogen atoms of theabove-described lower alkyl group is replaced by an amino group, and isspecifically exemplified by, for example, an aminomethyl group, anaminoethyl group, an aminopropyl group, an aminobutyl group, anamonopentyl group and an aminohexyl group.

The N-alkylcarbamoyl group includes one where a part of hydrogen atomsof the carbamoyl group is replaced by an alkyl group, and isspecifically exemplified by, for example, a N-methylcarbamoyl group, aN-ethylcarbamoyl group, a N-n-propylcarbamoyl group, aN-isopropylcarbamoyl group, a N-n-butylcarbamoyl group and aN-t-butylcarbamoyl group.

The hydroxylalkyl group includes one where a part of hydrogen atoms ofthe above-described lower alkyl group is replaced by a hydroxyl group,and is specifically exemplified by, for example, a hydroxymethyl group,a hydroxyethyl group, a hydroxypropyl group, a hydroxybutyl group, ahydroxypentyl group and a hydroxyhexyl group.

The aliphatic ring when R and R² or R¹ and R² form an aliphatic ringtogether with the adjacent —C═C— bond includes, for example, anunsaturated aliphatic ring having 5 to 10 carbon atoms, and the ring maybe monocyclic or polycyclic. Specific examples of these rings include,for example, a norbornene ring, a cyclopeantene ring, a cyclohexenering, a cyclooctene ring and a cyclodecene ring.

Specific examples of the monomer represented by the general formula [1]include, for example, ethylenically unsaturated aliphatic hydrocarbonshaving 2 to 20 carbon atoms such as ethylene, propylene, butylene andisobutylene; ethylenically unsaturated aromatic hydrocarbons having 8 to20 carbon atoms such as styrene, 4-methylstyrene, 4-ethylstyrene anddivinylbenzene; alkenyl esters having 3 to 20 carbon atoms such as vinylformate, vinyl acetate, vinyl propionate, isopropenyl acetate;halogen-containing ethylenically unsaturated compounds having 2 to 20carbon atoms such as vinyl chloride, vinylidene chloride, vinylidenefluoride and tetrafluoroethylene; ethylenically unsaturated carboxylicacids having 3 to 20 carbon atoms such as acrylic acid, methacrylicacid, itaconic acid, maleic acid, fumaric acid, crotonic acid,vinylacetic acid, allylacetic acid and vinylbenzoic acid (these acidsmay be in a form of salt with an ammonium or an alkali metal such assodium and potassium) ethylenically unsaturated carboxylic acid esterssuch as methyl methacrylate, ethyl methacrylate, propyl methacrylate,butyl methacrylate, 2-ethylhexyl methacrylate, methyl acrylate, ethylacrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, laurylmethacrylate, stearyl acrylate, methyl itaconate, ethyl itaconate,methyl maleate, ethyl maleate, methyl fumarate, ethyl fumarate, methylcrotonate, ethyl crotonate and methyl 3-butenate; cyan-containingethylenically unsaturated compounds having 3 to 20 carbon atoms such asacrylonitrile, methacrylonitrile and allyl cyanide; ethylenicallyunsaturated amid compounds having 3 to 20 carbon atoms such asacrylamide and methacrylamide; ethylenically unsaturated aldehydeshaving 3 to 20 carbon atoms such as acrolein and crotonaldehyde;ethylenically unsaturated sulfonic acids having 2 to 20 carbon atomssuch as vinylsulfonic acid and 4-vinylbenzenesulfonic acid (these acidsmay form an salt such as alkali metal salt with sodium or potassium);ethylenically unsaturated aliphatic amines having 2 to 20 carbon atomssuch as vinylamine and allylamine; etylenically unsaturated aromaticamines having 8 to 20 carbon atoms such as vinylaniline; ethylenicallyunsaturated aliphatic heterocyclic amines having 5 to 20 carbon atomssuch as N-vinylpyrolidone and vinylpiperidine; ethylenically unsaturatedalcohols having 3 to 20 carbon atoms such as allylalcohol andcrotylalcohol; and ethylenically unsaturated phenols having 8 to 20carbon atoms such as 4-vinylphenol.

The above-described skeletal polymer constructing the platinum catalystfixed on an ion-exchange resin preferably includes, for example, acopolymer of styrene based resin or acrylic ester based resincross-linked with a bifunctional monomer such as divinlbenzene,butadiene, isoprene, vinyl acrylate, vinyl methacrylate, allyl acrylate,allyl methacrylate, ethylene diacrylate, ethylene dimethacrylate,1,4-butanediol acrylate, 1,6-hexanediol acrylate, ethyleneglycoldimethacrylate, 1,3-butanediol dimethacryalte, triethyleneglycoldimethacrylate and N,N-methylene-bis(acrylamide), and specificallyexemplified by, for example, a styrene-divinylbenzene copolymer and amethyl acrylate-divinylbenzene copolymer.

The ion-exchange group bonded to the above-described skeletal polymer toform an ion-exchange resin includes, for example, a cation exchangegroup and an anion exchange group, and preferably an anion exchangegroup in the method of the present invention.

The above anion-exchange group includes, for example, a weak basicanion-exchange group and a strong basic anion-exchange group, and thecation-exchange group includes, for example, a weak acidiccation-exchange group and a strong acidic cation-exchange group.

Basic property of the anion-exchange resin is determined by basicproperty of the basic group constructing the anion-exchange group bondedto said anion-exchange resin. If said basic group is a weak basic group,the resin has weak basic property, and if the basic group is a strongbasic group, the resin has strong basic property. That is, basicproperty of the anion-exchange resin itself can be adjusted by properlyvarying basic property of the basic group.

Further, acidic property of the cation-exchange resin is determined byacidic property of the acidic group constructing the cation-exchangegroup bonded to said cation-exchange resin. If said acidic group is aweak acidic group, the resin has weak acidic property, and if the acidicgroup is a strong acidic group, the resin has strong acidic property.That is, acidic property of the cation-exchange resin itself can beadjusted by properly varying acidic property of the acidic group.

The anion-exchange group constructing the above-described ion-exchangeresin includes, for example, basic groups of amino groups such as aprimary amino group, a secondary amino group, a tertiary amino group anda quaternary amino group and diamines such as alkyldiamine. Amongothers, a tertiary amino group and a quaternary ammonium group arepreferable, and a quaternary ammonium group is particularly preferable.

In the above-described basic groups, for example, a primary amino group,a secondary amino group, a tertiary amino group and diamines are weakbasic anion-exchange groups, and for example, a quaternary ammoniumgroup is strong basic anion-exchange group.

In the anion-exchange group, the secondary amino group includes, forexample, one represented by the general formula [2]:

(wherein, R⁴ represents an alkyl group, an aryl group, an aralkyl groupor a hydroxyalkyl group), and the tertiary amino group includes, forexample, one represented by the following general formula [3]:

(wherein, R⁵ and R⁶ represent each independently an alkyl group, an arylgroup, an aralkyl group or a hydroxyalkyl group), and further thequaternary ammonium group includes, for example, one represented by thefollowing general formula [4]:

(wherein, R⁷, R⁸ and R⁹ represent each independently an alkyl group, anaryl group, an aralkyl group or a hydroxyalkyl group).

In the above-described general formulas [2], [3] and [4], the alkylgroup represented by R⁴ to R⁹ may be straight chained, branched orcyclic, and has generally 1 to 10 carbon atoms, preferably 1 to 6 carbonatoms, more preferably 1 to 4 carbon atoms, further more preferably 1 or2 carbon atoms, which is specifically exemplified by, for example, amethyl group, an ethyl group, a n-propyl group, an isopropyl group, an-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group,a n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentylgroup, a neopentyl group, a n-hexyl group, an isohexyl group, a3-methylpentyl group, a 2-methylpentyl group, a 1,2-dimethylbutyl group,a n-heptyl group, a n-isoheptyl group, a sec-heptyl group, a n-octylgroup, an isooctyl group, a sec-octyl group, a n-nonyl group, a n-decylgroup, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononylgroup and a cyclodecyl group.

In the general formulas [2], [3] and [4], the aryl group represented byR⁴ to R⁹ includes one having generally 6 to 10 carbon atoms andpreferably 6 carbon atoms, which is specifically exemplified by, forexample, a phenyl group and a naphtyl group. These aryl groups may havegenerally 1 to 5, preferably 1 to 2 substituents such as an alkyl groupand a hydroxyl group.

The alkyl group of the above-described aryl group which may have analkyl group may be straight chained, branched or cyclic, and includesone having generally 1 to 4 carbon atoms, preferably 1 to 2 carbonatoms, which is specifically exemplified by, for example, a methylgroup, an ethyl group, a n-propyl group, an isopropyl group, a n-butylgroup, an isobutyl group, a sec-butyl group, a tert-butyl group, acyclopropyl group and a cyclobutyl group.

In the general formulas [2], [3] and [4], the aralkyl group representedby R⁴ to R⁹ includes one having generally 7 to 10 carbon atoms, which isspecifically exemplified by, for example, a benzyl group, a phenylethylgroup, a phenylpropyl group and a phenylbutyl group.

In the general formulas [2], [3] and [4], the hydroxyalkyl grouprepresented by R⁴ to R⁹ includes, for example, one where one of hydrogenatoms of the above-described alkyl group represented by R⁴ to R⁹ isreplaced by a hydroxyl group, which is specifically exemplified by, forexample, a hydroxylmethyl group, a hydroxyethyl group, a hydroxypropylgroup, a hydroxybutyl group, a hydroxypentyl group, a hydroxyhexylgroup, a hydroxyheptyl group, a hydroxyoctyl group, a hydroxynonylgroup, a hydroxydecyl group, a hydroxycyclopropyl group, ahydroxycyclobutyl group, a hydroxycyclopentyl group, a hydroxycyclohexylgroup, a hydroxycycloheptyl group, a hydroxycyclooctyl group, ahydroxycyclononyl group and a hydroxycyclodecyl group. Among others, ahydroxymethyl group and a hydroxyethyl group are preferable, and ahydroxyethyl group is particularly preferable.

Particularly preferable specific examples of the tertiary amino grouprepresented by the above-described general formula [3] include thefollowing groups:

and particularly preferable specific examples of the quaternary ammoniumgroup represented by the above-described general formula [4] include thefollowing groups:

The above-described quaternary ammonium group is provided generally inan ionically bonded state with a suitable anion. The anion which isionically bonded to the quaternary ammonium group includes, for example,halogen ions such as a chloride ion, a bromide ion, a fluoride ion andan iodide ion, a hydroxide ion, a sulfate ion and an acetate ion. Amongothers, a chloride ion is preferable.

Further, the alkyldiamine group as the anion-exchange group includes agroup represented by the following general formula [5]:—NH—A—NH₂  [5](wherein, A represents an alkylene group).

In the general formula [5], the alkylene group represented by A may bestraight chained, branched or cyclic, preferably straight chained,having generally 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms,more preferably 1 to 4 carbon atoms and further more preferably 2 carbonatoms, which is specifically exemplified by, for example, a methylenegroup, an ethylene group, a trimethylene group, a propylene group, amethylmethylene group, a methylethylene group, an ethylmethylene group,a tetramethylene group, an ethylethylene group, a propylmethylene group,a pentamethylene group, a hexamethylene group, a heptamethylene group,an octamethylene group, a nonamethylene group, a decamethylene group, acyclopropylene group, a cyclobutylene group, a cyclopentylene group, acyclohexylene group, a cycloheptylene group, a cyclooctylene group, acyclononylene group and a cyclodecylene group.

Particularly preferable specific examples of the alkyldiamine grouprepresented by the above-described general formula [5] include, forexample, the following groups:

Further, the cation-exchange group constructing the above-describedion-exchange resin includes, for example, a sulfonic acid group and acarboxyl group. Among others, a sulfonic acid group is preferable.

In the above-described cation-exchange groups, for example, sulfonicacid group belongs to the strong acid cation-exchange groups, and, forexample, a carboxyl group and a phenolic hydroxyl group belong to theweak acid cation-exchange groups.

The most preferable specific examples of the ion-exchange group of theion-exchange resin used in the method of the present invention includethe following anion-exchange groups:

Preferable specific examples of the ion-exchange resin used in themethod of the present invention include, for example, an anion-exchangeresin consisting of a polystyrene copolymer cross-linked withdivinylbenzene which has the above-described anion-exchange group suchas a tertiary amino group or a quaternary ammonium group bonded to anaromatic ring thereof, and a polyacrylic ester which has theabove-described anion-exchange group such as a tertiary amino group or aquaternary ammonium group bonded to a carbonyl moiety of an ester groupthereof, and a cation-exchange resin consisting of a polystyrenecopolymer cross-linked with divinylbenzene which has the above-describedcation-exchange group such as a sulfonic acid group or a carboxyl groupbonded to an aromatic ring thereof and a polyacrylic ester which has theabove-described cation-exchange group such as a sulfonic acid group or acarboxyl group bonded to a carbonyl moiety of an ester group thereof.

The anion-exchange resin or the cation-exchange resin used in the methodof the present invention may be one which is synthesized by the knowntechnique or one on the market. Typical examples of the anion-exchangeresin on the market include, for example, DOWEX (Trade Name, made by DowChemical Co.), DUOLITE (Trade Name, made by Diamond Shamrock Corp.),AMBERLITE (Trade Name, made by Rohn & Haas Co.), NALCITE (Trade Name,made by Nalco Chemical Co.), IRA-410JC1 (Trade Name, made by OrganoCorp.), and IRA-400JC1 (Trade Name, made by Organo Corp.), and typicalexamples of the cation-exchange resin include, for example, IR-120B Na(Trade Name, made by Organo Corp.).

As described above, the platinum catalyst fixed on an ion-exchange resinof the present invention can be easily prepared by adsorbing theplatinum-containing ion, which is obtained by dissolving a platinumcompound in an aqueous solvent, on an ion-exchange resin as a carrier,followed by subjecting to a reductive treatment.

The aqueous solvent used for dissolving a platinum compound to obtainthe platinum catalyst fixed on an ion-exchange resin includes, forexample, alcohols having generally 1 to 4 carbon atoms such as methanol,ethanol, propanol and butanol; ketones such as acetone andmethylethylketone; esters such as ethyl acetate and butyl acetate;aqueous organic solvents such as acetonitrile and dimethylformamide, ora mixture thereof. Among others, a water-containing solvent ispreferable and water only is particularly preferable. Said aqueoussolvent may be properly added with an acid such as hydrochloric acid,sulfuric acid and nitric acid or a base such as sodium hydroxide andpotassium hydroxide to make the dissolution of a platinum compound easy.

Since all types of the platinum catalyst fixed on an ion-exchange resinof the present invention are similarly black colored in appearanceirrespective of a type of platinum compound used for preparationthereof, it is presumed that the platinum metal itself is fixed(immobilized or supported) on a matrix of an ion-exchange resin.

Amount of the platinum compound to be used for preparing the platinumcatalyst fixed on an ion-exchange resin of the present invention is anamount so that a ratio of the weight of Pt to the total weight of theplatinum catalyst fixed on an ion-exchange resin becomes generally0.0001 to 50% by weight, preferably 0.01 to 20% by weight, and morepreferably 0.01 to 10% by weight.

Herein below, the method for preparing the platinum catalyst fixed on anion-exchange resin will be described more specifically using a casewhere an anion-exchange resin is used as an example.

For example, a platinum compound which can release a platinum-containinganion such as K₂PtCl₄ is dissolved in an aqueous solvent containing amineral acid such as hydrochloric acid and sulfuric acid if necessary,followed by mixing said solution and an anion-exchange resin, thenleaving for standing if necessary. Then, the precipitates are filtered,washed and dried, followed by subjecting it to a reductive treatmentusing a suitable reducing agent such as hydrogen gas and hydrazine toobtain the platinum catalyst fixed on an anion-exchange resin of thepresent invention where the platinum metal is fixed on a matrix of ananion-exchange resin.

Further, herein below, the method for preparing the platinum catalystfixed on an ion-exchange resin will be described more specifically usinganother case where a cation-exchange resin is used as an example.

For example, a platinum compound which can release a platinum-containingcation such as [H₂NCH₂CH₂NH₂]Pt](NO₃)₂ is dissolved in an ion-exchangedwater, followed by mixing said solution and a cation-exchange resin,then leaving for standing if necessary. Then, the precipitates arefiltered, washed and dried, followed by subjecting it to a reductivetreatment using a suitable reducing agent such as hydrogen gas andhydrazine to obtain the platinum catalyst fixed on a cation-exchangeresin of the present invention where the platinum metal is fixed on amatrix of a cation-exchange resin.

The above-described reducing agent used for manufacturing the platinumcatalyst fixed on an ion-exchange resin may be a compound generally usedas a reducing compound. Among others, preferable specific examplesinclude, for example, hydrogen gas, hydrazine, sodium hydroborate,ammonium formate, diethylammonium formate, sodium hypophosphite,potassium hypophosphite, carbon monoxide and ethylene.

Temperature of the reductive treatment is generally −20 to 200° C.,preferably 0 to 100° C., and more preferably 10 to 60° C., and thereductive treatment may be carried out in accordance with the knownmethod.

The objective hydroxylamine compound can be obtained by contacting anitro compound with a hydrogen source in the presence of the thusobtained platinum catalyst fixed on an ion-exchange resin.

In the method of the present invention, the nitro compound includes, forexample, a compound represented by the general formula [6]:R¹⁰—NO₂  [6](wherein, R¹⁰ represents an alkyl group, an aryl group or an aralkylgroup which may contain a hydrogen atom or a hetero atom and also have asubstituent).

In the general formula [6], the alkyl group represented by R¹⁰ may bestraight chained, branched or cyclic one having generally 1 to 40 carbonatoms, preferably 1 to 20 carbon atoms, more preferably 1 to 10 carbonatoms and further more preferably 1 to 6 carbon atoms, which isspecifically exemplified by, for example, straight chained or branchedgroups such as a methyl group, an ethyl group, a n-propyl group, anisopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, a n-pentyl group, an isopentyl group, a sec-pentylgroup, a tert-pentyl group, a neopentyl group, a n-hexyl group, anisohexyl group, a sec-hexyl group, a tert-hexyl group, a n-heptyl group,an isoheptyl group, a sec-heptyl group, a tert-heptyl group, a n-octylgroup, a sec-octyl group, a tert-octyl group, a nonyl group, a decylgroup, a undecyl group, a dodecyl group, a tridecyl group, a tetradecylgroup, a pentadecyl group, a hexadecyl group, a heptadecyl group, anoctadecyl group, a nonadecyl group, an icosyl group, a docosyl group, atetracosyl group, apentacosyl group, aheptacosyl group, a triacontylgroup, a dotriacontyl group, a hexacontyl group and an octacontyl group;saturated aliphatic monocyclic groups such as a cyclopropyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, a cyclononyl group, a cyclodecyl group, a cycloundecyl group, acyclododecyl group, a cyclotridecyl group, a cyclotetradecyl group, acyclopentadecyl group, a cyclohexadecyl group, a cycloheptadecyl group,a cyclooctadecyl group, a cyclononadecyl group and a cycloicosyl group;unsaturated aliphatic monocyclic groups such as a cyclobutenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, acyclooctenyl group and a cyclononenyl group; saturated or unsaturatedaliphatic polycyclic groups such as a tricyclodecyl group, adicyclopentadienyl group, a perhydronaphthyl group, a perhydroanthrylgroup, a norbornyl group, a norpinyl group, a norcaranyl group and anadamantyl group.

The aryl group represented by R¹⁰ includes one having generally 6 to 14carbon atoms and preferably 6 to 10 carbon atoms, which is specificallyexemplified by, for example, a phenyl group, a naphthyl group and ananthryl group.

The aralkyl group represented by R¹⁰ includes one having generally 7 to10 carbon atoms, which is specifically exemplified by, for example, abenzyl group, a phenylethyl group, a phenylpropyl group and aphenylbutyl group.

The above-described alkyl group, aryl group and aralkyl grouprepresented by R¹⁰ may contain generally 1 to 10 hetero atoms,preferably 1 to 3 hetero atoms and more preferably one hetero atom.These hetero atoms include, for example, oxygen atom, sulfur atom andnitrogen atom, which are present in the group in a form of a group suchas —NH—, —O—, —S—, —NHR— (wherein R represents an alkyl group, an arylgroup or an aralkyl group) —N═, —C(═O)—NH—, —S(═O)—NH—, —C(═O)— and—S(═O)—.

Here, an alkyl group, an aryl group and an aralkyl group represented byR of the group shown by —NHR— include the similar one to an alkyl group,an aryl group and an aralkyl group represented by R⁴ of theabove-described general formula [2].

Further, the alkyl group represented by R¹⁰ may have generally 1 to 10substituents, preferably 1 to 5 substituents and more preferably 1 to 3substituents. These substituents include, for example, alkoxy groupshaving 1 to 6 carbon atoms such as a methoxy group, an ethoxy group, apropyloxy group, a butoxy group, a pentyloxy group and a hexyloxy group;halogen atoms such as chlorine atom, bromine atom, fluorine atom andiodine atom; a hydroxyl group; and an amino group.

The aryl group and the aralkyl group represented by R¹⁰ may havegenerally 1 to 10 substituents, preferably 1 to 5 substituents and morepreferably 1 to 3 substituents. These substituents include, for example,straight chained branched or cyclic alkyl group having 1 to 6 carbonatoms such as a methyl group, an ethyl group, a n-propyl group, anisopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, a n-pentyl group, an isopentyl group, a sec-pentylgroup, a tert-pentyl group, a neopentyl group, a n-hexyl group, anisohexyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentylgroup and a cyclohexyl group; alkoxy groups having 1 to 6 carbon atomssuch as a methoxy group, an ethoxy group, a propyloxy group, a butoxygroup, a pentyloxy group and a hexyloxy group; halogen atoms such aschlorine atom, bromine atom, fluorine atom and iodine atom; a hydroxylgroup; and an amino group.

In the above-described nitro compound represented by the general formula[6], R¹⁰ is preferably an aryl group. Among others, nitrobenzenederivatives such as nitrobenzene, nitrotoluene and nitroxylene arepreferable, and nitrobenzene is particularly preferable.

The hydrogen source in the method of the present invention includes, forexample, gases such as hydrogen, carbon monoxide and ethylene; alcoholssuch as methanol, ethanol, isopropyl alcohol and butanol; hydrazinessuch as hydrazine, methylhydrazine, ethylhydrazine, tert-butylhydrazine,allylhydrazine and phenylhydrazine or salts thereof (for example,hydrochloride, sulfate, acetate and oxalate thereof); carboxylic acidssuch as formic acid and acetic acid; or salts thereof (for example,alkali metal salts such as sodium salt and potassium salt);hypophosphites such as sodium hypophosphite and potassium hypophosphite;ammonium formate; decaline; and formaldehyde. Among others, hydrazinesare preferable, and hydrazine is particularly preferable. As theabove-described hydrazines, hydrates thereof and hydrazines containingwater in advance can also be used.

Amount of the hydrogen source to be used is generally 1 to 100 times bymole and preferably 1 to 50 times by mole to the nitro compound which isa reaction substrate in the method of the present invention. Whenhydrazine is used as a hydrogen source, an amount of hydrazine to beused is generally 1 to 100 times by mole, preferably 1 to 50 times bymole, and more preferably 1 to 10 times by mole to the nitro compound.

When hydrazines are used as a hydrogen source, said hydrazines may beused as they are in the method of the present invention, but preferablythey may be used after dissolving in water so that concentrations ofsaid hydrazines become generally 10 to 100% by weight and preferably 50to 100% by weight.

Amount of the platinum catalyst fixed on an ion-exchange resin to beused is such one that an amount of the platinum fixed becomes generally1.0×10⁻⁶ to 1 times by mole and preferably 1.0×10⁻⁴ to 0.4 times by moleto the nitro compound which is a substrate.

In the method of the present invention, it may be possible that furtheraddition of a poisoning agent (generally designated as a catalyticpoison substance) against the catalytic action of the platinum catalystfixed on an ion-exchange resin to the reaction system further improveselectivity of hydroxylamine.

The poisoning agent includes, for example, sulfur-containing compoundssuch as dimethyl sulfoxide and diethyl sulfoxide; heavy metal ions suchas a mercury ion, an arsenic ion, a lead ion, a bismuth ion and anantimony ion; halides such as sodium iodide and potassium iodide; aminessuch as trimethylamine, triethylamine, pyridine and morpholine;phosphines such as triphenylphosphine,diphenyl(tert-butyl)phosphinomethane, diphenyl(tert-butyl)phosphinoethane and diphenyl(tert-butyl)phosphinopropane; carbonmonoxide; and carbon dioxide. Among others, sulfur-containing compoundsare preferable, and dimethyl sulfoxide is particularly preferable.

Amount of the poisoning agent to be used is generally 0 to 100% byweight, preferably 0 to 30% by weight, and more preferably 0 to 10% byweight.

When the nitro compound, the hydrogen source and the like to be used inthe method of the present invention are liquid, further use of areaction solvent may not be required because these substances play arole of solvent.

The reaction solvent includes, for example, water and an organic solventsuch as alcohols such as methanol, ethanol, n-propanol, isopropanol,n-butanol, isobutanol, sec-butanol and tert-butanol; ketones such asacetone and methyl ethyl ketone; nitrites such as acetonitrile andbutyronitrile; halogenated hydrocarbons such as dichloromethane,1,2-dichloroethane, chloroform and carbon tetrachloride; ethers such asdiethyl ether, dimethoxyethane, diethoxyethane and tetrahydrofuran;hydrocarbons such as n-hexane, n-heptane and cyclohexane; aromatichydrocarbons such as benzene, toluene and xylene; esters such as ethylacetate and butyl acetate. These solvents may be used alone or in aproper combination of 2 or more types. Further, selectivity of thereaction can be varied by a reaction solvent or a combination thereof tobe used.

When water and an organic solvent are used in combination, ratio ofwater to the organic solvent is generally 0.0001 to 100 times by weight,preferably 0.001 to 100 times by weight, more preferably 0.01 to 50times by weight, and further more preferably 0.01 to 20 times by weight.

Amount of the reaction solvent to be used is generally 1 to 50 times byweight, preferably 1 to 20 times by weight, and more preferably 1 to 10times by weight to the nitro compound which is a reaction substrate.

In the method of the present invention, any reaction method of batch,semi-batch and continuous methods of suspension bed system or flow onfixed bed system may be used so long as surface of the platinum catalystfixed on an ion-exchange resin in the reaction vessel is contacted withliquid of raw material and the like.

Reaction temperature is generally −20 to 200° C., preferably 10 to 100°C., and more preferably 10 to 70° C.

Reaction time is generally 1 minute to 24 hours, preferably 10 minutesto 16 hours, and more preferably 30 minutes to 12 hours.

Reaction pressure is generally atmospheric pressure to 10 MPa andpreferably atmospheric pressure to 2 MPa.

Thus, hydroxylamine compound can be obtained, for example, by mixing anitro compound as a substrate with about 1 to 50 times by weight of asolvent to said nitro compound, adding thereto a platinum catalyst fixedon an anion-exchange resin so that platinum present in the catalystbecomes 1×10⁻⁶ to 1 times by mole, and further adding hydrazine in anamount of 1 to 100 times by mole to the nitro compound as a substrateand a poisoning agent in an amount of 0 to 100% by weight to the nitrocompound as a substrate, followed by reacting under reflux for about 1minute to 24 hours with stirring, after completion of the reaction,removing the platinum catalyst fixed on an anion-exchange resin byfiltering, concentrating the reaction liquid, and purifying ifnecessary.

By the above-described method of the present invention, a nitro group ofthe nitro compound represented by the above general formula [6] isconverted to a hydroxyamono group to give a corresponding hydroxylaminecompound represented by the general formula [7]:R¹⁰—NHOH  [7](wherein, R¹⁰ represents the same as the above)

In the method of the present invention, the hydroxyamino group of theobjective hydroxylamine compound represented by the general formula [7]is sometimes reduced to an amino group as similarly seen in theconventional method. However, since formation ratio of the byproduct isextremely lower compared to the conventional method, the objectivehydroxylamine compound can be obtained in very high yield. Further, asdescribed above, the platinum catalyst fixed on an ion-exchange resinwhich was used in the reaction can be isolated from the reaction liquidafter the reaction and repeatedly reused as a catalyst for variousreactions without losing activity thereof. Still further, since particlesize of the platinum catalyst fixed on an ion-exchange resin of thepresent invention is very large, handling of said catalyst in recoveryand reuse thereof is very easy.

Herein below, the present invention will be explained in more detailusing Examples, but the present invention is not limited thereto by anymeans.

EXAMPLES Example 1 Synthesis of a Platinum Catalyst Fixed on anAnion-Exchange Resin of the Present Invention

To 62.5 mL of 1N hydrochloric acid solution containing 9.6×10⁻³M ofK₂PtCl₄, 15 g of an anion-exchange resin made of styrene/divinylbenzenecopolymer having a group represented by the following formula:

as an ion-exchange group (Trade Name: IRA-410JC1, made by Organo Corp.)was added at room temperature under stirring, and the reaction liquidwas subjected to a reaction for 10 minutes at the same temperature understirring. After completion of the reaction, the resin was washed withmethanol and water in this order. Further, 50 mL of water and 0.2 mL ofhydrazine were added thereto at room temperature, followed by reactingfor 1 hour under stirring. After completion of the reaction, the resinwas washed with methanol and water in this order, then vacuum dried toobtain 15.2 g of black colored platinum catalyst fixed on anion-exchange resin. The amount of platinum supported in the platinumcatalyst fixed on an ion-exchange resin obtained was about 1% by weightfrom the result of measurement by weight change.

Example 2 Synthesis of a Platinum Catalyst Fixed on an Anion-ExchangeResin of the Present Invention

To 62.5 mL of 1N hydrochloric acid solution containing 9.6×10⁻³M ofK₂PtCl₄, 15 g of an anion-exchange resin made of styrene/divinylbenzenecopolymer having a group represented by the following formula:

as an ion-exchange group (Trade Name: IRA-400JC1, made by Organo Corp.)was added at room temperature under stirring, and the reaction liquidwas subjected to a reaction for 10 minutes at the same temperature understirring. After completion of the reaction, the resin was washed withmethanol and water in this order. Further, 50 mL of water and 0.2 mL ofhydrazine were added thereto at room temperature, followed by reactingfor 1 hour under stirring. After completion of the reaction, the resinwas washed with methanol and water in this order, then vacuum dried toobtain 15.2 g of black colored platinum catalyst fixed on anion-exchange resin. The amount of platinum supported in the platinumcatalyst fixed on an ion-exchange resin obtained was about 1% by weightfrom the result of measurement by weight change.

Example 3 Synthesis of a Platinum Catalyst Fixed on a Cation-ExchangeResin of the Present Invention

To 62.5 mL of an aqueous solution containing 9.6×10⁻³M of[(H₂NCH₂CH₂NH₂Pt](NO₃)₂, 15 g of a regenerated cation-exchange resinmade of styrene/divinylbenzene copolymer having a sulfonic acid group asan ion-exchange group (Trade Name: IR-120B Na, made by Organo Corp.) wasadded at room temperature under stirring, and the reaction liquid wassubjected to a reaction for 10 minutes at the same temperature understirring. After completion of the reaction, the resin was washed withmethanol and water in this order. Further, 50 mL of water and 0.2 mL ofhydrazine were added thereto at room temperature, followed by reactingfor 1 hour under stirring. After completion of the reaction, the resinwas washed with methanol and water in this order, then vacuum dried toobtain 15.2 g of black colored platinum catalyst fixed on anion-exchange resin. The amount of platinum supported in the platinumcatalyst fixed on an ion-exchange resin obtained was about 1% by weightto the whole catalyst from the result of measurement by weight change.

Example 4 Synthesis of a Platinum Catalyst Fixed on a Cation-ExchangeResin of the Present Invention

To 62.5 mL of an aqueous solution containing 9.6×10⁻³M of[(H₂NCH₂CH₂NH₂) Pt]Cl₂, 15 g of a regenerated cation-exchange resin madeof styrene/divinylbenzene copolymer having a sulfonic acid group as anion-exchange group (Trade Name: IR120B Na, made by Organo Corp.) wasadded at room temperature with stirring, and the reaction liquid wassubjected to a reaction for 10 minutes at the same temperature understirring. After completion of the reaction, the resin was washed withmethanol and water in this order. Further, 50 mL of water and 0.2 mL ofhydrazine were added thereto at room temperature, followed by reactingfor 1 hour under stirring. After completion of the reaction, the resinwas washed with methanol and water in this order, then vacuum dried toobtain 15.2 g of black colored platinum catalyst fixed on anion-exchange resin. The amount of platinum supported in the platinumcatalyst fixed on an ion-exchange resin obtained was about 1% by weightto the whole catalyst from the result of measurement by weight change.

Example 5 Synthesis of a Hydroxylamine Compound of the Present Invention

Into a reaction vessel, 10 mL of nitrobenzene (98 mmol), 100 mL ofisopropyl alcohol, 0.05 mL of dimethylsulfoxide and 4 g of the platinumcatalyst fixed on an ion-exchange resin obtained in Example 1 werecharged, and 20 mL of hydrazine was added thereto dropwise over 1 hour,followed by reacting the reaction liquid under reflux for 4 hours understirring. After completion of the reaction, the platinum catalyst fixedon an ion-exchange resin in the reaction liquid was removed byfiltration, and the solution obtained was concentrated followed byrecrystallization in isopropyl alcohol to obtain 10 g ofphenylhydroxylamine (yield 95%).

The obtained compound was confirmed to be phenylhydroxylamine by the¹H-NMR spectrum measurement.

Example 6 Synthesis of a Hydroxylamine Compound of the Present Invention

Into a reaction vessel, 10 mL of nitrobenzene (98 mmol), 100 mL ofmethanol, 0.05 mL of dimethylsulfoxide and 4 g of the platinum catalystfixed on an ion-exchange resin obtained in Example 1 were charged, and20 mL of hydrazine was added thereto dropwise over 1 hour, followed byreacting the reaction liquid under reflux for 4 hours under stirring.After completion of the reaction, the platinum catalyst fixed on anion-exchange resin in the reaction liquid was removed by filtration, andthe solution obtained was concentrated followed by recrystallization inmethanol to obtain 9.7 g of phenylhydroxylamine (yield 92%).

The obtained compound was confirmed to be phenylhydroxylamine by the¹H-NMR spectrum measurement.

Example 7

After the same reaction procedures as in Example 6 proceeded, theplatinum catalyst fixed on an ion-exchange resin was removed from thereaction liquid by filtration, and volume of the mother liquid wasadjusted exactly to 100 mL, which was analyzed by a high performanceliquid chromatography to obtain, by calculation remaining ratio ofnitrobenzene as a raw material, yield of the obtainedphenylhydroxylamine and formation ratio of aniline as a byproduct. Theplatinum catalyst fixed on an ion-exchange resin filtered out wasrepeatedly used for the same reaction several times after washing withmethanol. The reaction liquid after completion of each reaction wasanalyzed by a high performance liquid chromatography in the same manneras described above to obtain ratios of responding in each reaction(remaining ratio of nitrobenzene, yield of phenylhydroxylamine andformation ratio of aniline). Results are shown in Table 1.

TABLE 1 Number of repeated use of Ratio of responding (%) the catalystNitrobenzene Phenylhydroxylamine Aniline 1 0.5 97.2 2.2 2 0.9 96.1 3.0 31.1 97.9 1.0 4 2.2 96.3 1.5 5 1.6 96.1 2.2 6 0.7 97.7 1.6 7 0.7 97.2 2.1

As clear from Table 1, it was proved that even if the platinum catalystfixed on an ion-exchange resin of the present invention was usedrepeatedly for the reaction, yield of the objective phenylhydroxylaminedid not decrease and formation ratio of the byproduct was alsomaintained at low level. From the results, it is understood that theplatinum catalyst fixed on an ion-exchange resin of the presentinvention is hardly deactivated by the repeated use.

INDUSTRIAL APPLICABILITY

According to the method of the present invention where a platinumcatalyst fixed on a matrix of an ion-exchange resin is used, theobjective hydroxylamine compound can be manufactured efficiently, moreindustrially and safely with little formation of a byproduct. Further,the platinum catalyst fixed on an ion-exchange resin of the presentinvention is hardly deactivated even if repeatedly used many timesbecause platinum metal is fixed on a matrix of the ion-exchange resin,and handling in recovery, reuse and the like of said catalyst isextremely easy because particle size of said catalyst is very large.

1. A method for producing a hydroxylamine compound, comprising:contacting a nitro compound with a hydrogen source in the presence of aplatinum catalyst fixed on an ion-exchange resin, wherein the hydrogensource is hydrazine and the platinum catalyst fixed on an ion-exchangeresin is obtained by adsorbing a platinum-containing ion in an aqueoussolvent derived from a platinum compound with the ion-exchange resinfollowed by subjecting the ion to a reductive treatment, and theplatinum compound is selected from the group consisting of ammoniumhexachloroplatinate, ammonium tetrachloroplatinate, potassiumhexachloroplatinate, potassium tetrachloroplatinate, potassiumtetrabromoplatinate, sodium hexachloroplatinate, sodiumtetrachloroplatinate, platinum nitrate, platinum sulfate, platinumacetate, and platinum complexes coordinated with a ligand selected fromthe group consisting of 1,5-cyclooctadiene (COD), dibenzylideneacetone(DBA), norbornadiene (NBD), tricyclohexylphosphine (PCγ₃),triethoxyphosphine (P(OEt)₃, tri-tert-butylphosphine (P(O′Bu)₃,bipyridine (BPY), phenanthroline (PHE), triphenylphosphine (PPh₃),1,2-bis(diphenylphosphino)ethane (DPPE), triphenoxyphosphine (P(OPh)₃),trimethoxyphosphine (P(OCH₃)₃), ethylene (CH₂═CH₂), amine(NH₃), N₂ andPO₃.
 2. The method according to claim 1, wherein the nitro compound is anitrobenzene derivative.
 3. The method according to claim 1, wherein anitro compound is further contacted with a poisoning agent.
 4. Themethod according to claim 3, wherein the poisoning agent isdimethylsulfoxide.
 5. The method according to claim 1, wherein anion-exchange resin used in preparation of the platinum catalyst fixed onan ion-exchange resin is a polystyrene copolymer cross-linked withdivinylbenzene which has an ion-exchange group bonded to an aromaticring thereof.
 6. The method according to claim 1, wherein anion-exchange resin used in the preparation of the platinum catalystfixed on an ion-exchange resin is a polyacrylic ester which has anion-exchange group bonded to a carbonyl moiety of an ester groupthereof.
 7. The method according to claim 5 or 6, wherein theion-exchange group is an anion-exchange group.
 8. The method accordingto claim 7, wherein the anion-exchange group is selected from the groupconsisting of a primary amino group, a secondary amino group, a tertiaryamino group, a quaternary ammonium group and an alkyldiamine group. 9.The method according to claim 8, wherein the tertiary amino group isselected from the group consisting of a dimethylamino group, amethylethylamino group and a diethylamino group, and the quaternaryammonium group is selected from the group consisting of the followinggroups:


10. The method according to claim 5 or 6, wherein the ion-exchange groupis a cation-exchange group.
 11. The method according to claim 10,wherein the cation-exchange group is selected from the group consistingof a sulfonic acid group, a carboxyl group and a phenolic hydroxylgroup.
 12. The method according to claim 3, wherein amount of thepoisoning agent is 1 to 30% by weight to the nitro compound.
 13. Themethod according to claim 1, wherein the platinum compound is potassiumtetrachloroplatinate or sodium tetrachloroplatinate.
 14. The methodaccording to claim 1, wherein yield of hydroxylamine is 90% and over.